Decrement character with php

Question

Why is it that it\'s ok to increment character but not decrement with PHP?

PHP

Answer 1

As chris85 mentioned: "Character variables can be incremented but not decremented"

---

PHP supports C-style pre- and post-increment and decrement operators.

Incrementing/Decrementing Operators

1. ++$a Pre-increment Increments $a by one, then returns $a.
2. $a++ Post-increment Returns $a, then increments $a by one.
3. --$a Pre-decrement Decrements $a by one, then returns $a.
4. $a-- Post-decrement Returns $a, then decrements $a by one.

Note: The increment/decrement operators only affect numbers and strings. Arrays, objects and resources are not affected. Decrementing NULL values has no effect too, but incrementing them results in 1.

---

SRC: http://php.net/manual/en/language.operators.increment.php

Answer 2

There is no direct way to decrement alphabets. But with a simple function you can achieve it:

function decrementLetter($Alphabet) {
    return chr(ord($Alphabet) - 1);
}

Source, thanks to Ryan O'Hara

Answer 3

Simple function you can achieve it:

function decrementChar($Alphabet) {
return chr(ord($Alphabet) - 1);
}

Answer 4

Please try with this. Output is a b a.

$a = "a";
echo $a. "<br>";  
echo $next = chr(ord($a) + 1). "<br>";
echo $prev = chr(ord($next) - 1 ). "<br>"; 

Answer 5

There is no simple way, especially if you start with multi-character strings like 'AA'.

As far as I can ascertain, the PHP Internals team couldn't decide what to do when

$x = 'A';
$x--;

so they simply decided not to bother implementing the character decrementor logic